Structural consequences of proton transfer in some selected complexes of phenol derivatives with trimethylamine

General tendencies in structure modifications resulting from proton transfer in complexes of six selected phenols with trimethylamine are established on the basis of DFT B3LYP/6-31G(d,p) calculations with complete optimization of the structure for a given OH distance. found that various parameters linearly depend on C–O distance (d(CO)). Separate correlation lines are obtained for the complexes of different phenols. Values d(CO) depend on substitution and are proportional to pKa. The O–H distance does not depend on pKa in free phenols, but is strongly sensitive, while is engaged into hydrogen bond.